DOCSLIB.ORG

The Stringent Response Regulates Adaptation to Darkness In

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Stringent Response Regulates Adaptation to Darkness In The stringent response regulates adaptation to darkness PNAS PLUS in the cyanobacterium Synechococcus elongatus Rachel D. Hooda, Sean A. Higginsa, Avi Flamholza, Robert J. Nicholsa, and David F. Savagea,b,c,1 aDepartment of Molecular and Cell Biology, University of California, Berkeley, CA 94720; bDepartment of Chemistry, University of California, Berkeley, CA 94720; and cEnergy Biosciences Institute, University of California, Berkeley, CA 94720 Edited by Robert Haselkorn, University of Chicago, Chicago, IL, and approved June 27, 2016 (received for review December 17, 2015) The cyanobacterium Synechococcus elongatus relies upon photosynthe- provided insight into regulatory strategies that persist in constant sis to drive metabolism and growth. During darkness, Synechococcus light, but few studies have addressed the mechanisms by which stops growing, derives energy from its glycogen stores, and greatly cells adapt to darkness, predictable or otherwise. decreases rates of macromolecular synthesis via unknown mechanisms. Nearly all aspects of cyanobacterial physiology are affected by Here, we show that the stringent response, a stress response path- a shift from light to dark: cells stop elongating and dividing, cease way whose genes are conserved across bacteria and plant plastids, DNA replication, and exhibit decreased rates of transcription and contributes to this dark adaptation. Levels of the stringent response translation (5–7). Proteins produced in the dark differ from those alarmone guanosine 3′-diphosphate 5′-diphosphate (ppGpp) rise produced in the light (8), and recent studies have identified genes after a shift from light to dark, indicating that darkness triggers the that are differentially expressed between light and dark (9, 10). same response in cyanobacteria as starvation in heterotrophic bacte- How the cell coordinates these transcriptional and translational ria. High levels of ppGpp are sufficient to stop growth and dramati- changes remains largely unknown. cally alter many aspects of cellular physiology, including levels of Not only does Synechococcus physiology change a great deal photosynthetic pigments and polyphosphate, DNA content, and the between light and dark, but its metabolism also shifts dramati- rate of translation. Cells unable to synthesize ppGpp display pro- cally. Photosynthetically active cells reduce carbon dioxide into nounced growth defects after exposure to darkness. The stringent carbohydrates, which they accumulate as glycogen. When light is response regulates expression of a number of genes in Synechococcus, no longer available, cells catabolize their glycogen stores through including ribosomal hibernation promoting factor (hpf), which causes respiration. Metabolism must be tightly controlled in the dark MICROBIOLOGY ribosomes to dimerize in the dark and may contribute to decreased because total energy supply is finite and must be rationed (5), translation. Although the metabolism of Synechococcus differentiates which raises the question of whether dark periods are analogous it from other model bacterial systems, the logic of the stringent re- to starvation for Synechococcus and whether bacterial stress re- sponse remains remarkably conserved, while at the same time having adapted to the unique stresses of the photosynthetic lifestyle. sponse mechanisms mediate adaptation to darkness. Here, we show that the stringent response—a stress response cyanobacteria | Synechococcus | stringent response | (p)ppGpp | pathway whose enzymes are conserved in nearly all bacteria, as well — hibernation promoting factor as plant plastids is involved in dark adaptation in Synechococcus. We find that this pathway is active in Synechococcus and that it exerts dramatic effects on cellular physiology. Furthermore, this he conversion of solar light energy to chemical energy through response is required for cells to adapt properly to darkness, as cells photosynthesis ultimately supports the majority of life on Earth. T lacking the stringent response display pronounced growth defects Light harvesting by photosynthetic antenna complexes and pho- in diurnal light/dark cycles and loss of viability after prolonged tosystems is directly tied to light availability, which can fluctuate greatly over the course of a single day (1). The growth and re- exposure to darkness. We investigate which genes are regulated production of photosynthetic organisms therefore depend upon their ability to capture light efficiently, and they have evolved Significance several mechanisms that allow them to adapt to changing light conditions (2). Cyanobacteria are an important group of photosynthetic bac- Cyanobacteria comprise a diverse bacterial phylum that oxygen- teria that rely upon light energy for growth but frequently must ated the atmosphere, gave rise to the plant chloroplast, and that adapt to darkness. Cells stop growing and decrease overall rates performs 10 to 25% of global photosynthesis today. Synechococcus of gene expression and protein synthesis in the dark, but the elongatus PCC 7942 (hereafter, Synechococcus) is a model cyano- molecular mechanisms behind these observations remain un- bacterium that relies exclusively upon photosynthesis and carbon known. We find that a widespread bacterial stress response, the assimilation to grow. Its obligate photoautotrophic lifestyle stringent response, helps cells conserve resources during darkness. makes Synechococcus a useful system in which to investigate the In the dark, cells produce higher levels of the stringent response ′ ′ coordination and regulation of these inherently essential meta- signaling molecule guanosine 3 -diphosphate 5 -diphosphate bolic processes. (ppGpp), thereby altering gene expression patterns and affecting Cyanobacteria frequently encounter transitions between light the protein synthesis machinery. These results help explain pre- and dark in their environment, and these transitions fall into two vious observations in the cyanobacterial literature and extend our distinct categories. One is due to the rising and setting of the sun, knowledge of how the same signaling pathway has been adapted which yields predictable transitions from light to dark and back to different bacterial lifestyles and metabolisms. to light again. Synechococcus has a circadian rhythm that antic- Author contributions: R.D.H., S.A.H., and D.F.S. designed research; R.D.H., S.A.H., and ipates the timing of dawn and dusk and regulates the expression R.J.N. performed research; R.D.H., S.A.H., and R.J.N. contributed new reagents/analytic of a majority of its genes in a time-dependent manner (3, 4). The tools; R.D.H., S.A.H., A.F., and D.F.S. analyzed data; and R.D.H. and D.F.S. wrote the paper. second type of light/dark transition is unpredictable and can The authors declare no conflict of interest. occur due to transient cloud cover or shade cast by other or- This article is a PNAS Direct Submission. ganisms or geological features, for example. These transitions 1To whom correspondence should be addressed. Email: [email protected]. cannot be anticipated, and may require a rapid restructuring of This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. metabolism. Studies of circadian rhythm in Synechococcus have 1073/pnas.1524915113/-/DCSupplemental. www.pnas.org/cgi/doi/10.1073/pnas.1524915113 PNAS | Published online August 2, 2016 | E4867–E4876 Downloaded by guest on September 27, 2021 AB∼150 μM. We find, therefore, that ppGpp levels increase rap- idly in Synechococcus in response to darkness. 10 To artificially increase (p)ppGpp levels, we constructed a 20 Synechococcus strain that inducibly expresses a small (p)ppGpp synthetase from Bacillus subtilis, yjbM/SAS1. This gene has been 5 heterologously expressed in E. coli and resulted in high levels of + 10 (p)ppGpp (15). We refer to this strain as “ppGpp .” As expected, + the ppGpp strain had significantly higher ppGpp levels in the light 0 not detected than a control harboring an empty plasmid, as measured by HPLC 32 ppGpp peak area (AU) relative ppGpp peak area – 0 + -L and P-TLC (Fig. 1B and SI Appendix, Fig. S1 B D). Based on -D5 0 30 60 90 120 150 rel the crystal structure and mutational studies of the homologous control-L Time (minutes) ppGppcontrol-D5 Rel (p)ppGpp synthetase from Streptococcus equisimilus (16), we generated a point mutant, D72G, to abrogate the activity of the Fig. 1. ppGpp levels increase in the dark in Synechococcus and can be ge- B. subtilis synthetase. A recent crystal structure of yjbM/SAS1 netically manipulated. (A) Synechococcus cultures were shifted from the revealed that Asp72 coordinates a magnesium ion required for light (white background) to the dark (gray background) at 0 min and were catalytic activity (17). The D72G mutation did indeed inactivate harvested at the time points shown. Extracts were analyzed by anion ex- change HPLC (AU, arbitrary units). Peaks eluting at the same time as a ppGpp (p)ppGpp synthetic activity, restoring ppGpp levels to those of the empty plasmid control (SI Appendix, Fig. S1 C and D). We standard were integrated to determine relative ppGpp levels. (B) Analysis of + ppGpp levels from Synechococcus strains in the light (L) and the dark (D). refer to this strain as “ppGpp D72G.” Using these strains, we Cultures harvested in the light were induced with IPTG for 17 h (control, WT- can control (p)ppGpp synthesis in Synechococcus, allowing us to CmR). Cultures in the dark were harvested 5 min after the light-to-dark shift. investigate the
Load more

Recommended publications
  • Characteristic Microbiomes Correlate with Polyphosphate Accumulation of Marine Sponges in South China Sea Areas
    microorganisms Article Characteristic Microbiomes Correlate with Polyphosphate Accumulation of Marine Sponges in South China Sea Areas 1 1, 1 1 2, 1,3, Huilong Ou , Mingyu Li y, Shufei Wu , Linli Jia , Russell T. Hill * and Jing Zhao * 1 College of Ocean and Earth Science of Xiamen University, Xiamen 361005, China; [email protected] (H.O.); [email protected] (M.L.); [email protected] (S.W.); [email protected] (L.J.) 2 Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD 21202, USA 3 Xiamen City Key Laboratory of Urban Sea Ecological Conservation and Restoration (USER), Xiamen University, Xiamen 361005, China * Correspondence: [email protected] (J.Z.); [email protected] (R.T.H.); Tel.: +86-592-288-0811 (J.Z.); Tel.: +(410)-234-8802 (R.T.H.) The author contributed equally to the work as co-first author. y Received: 24 September 2019; Accepted: 25 December 2019; Published: 30 December 2019 Abstract: Some sponges have been shown to accumulate abundant phosphorus in the form of polyphosphate (polyP) granules even in waters where phosphorus is present at low concentrations. But the polyP accumulation occurring in sponges and their symbiotic bacteria have been little studied. The amounts of polyP exhibited significant differences in twelve sponges from marine environments with high or low dissolved inorganic phosphorus (DIP) concentrations which were quantified by spectral analysis, even though in the same sponge genus, e.g., Mycale sp. or Callyspongia sp. PolyP enrichment rates of sponges in oligotrophic environments were far higher than those in eutrophic environments.
    [Show full text]
  • Photosymbiosis for Biomedical Applications
    fbioe-08-577204 October 3, 2020 Time: 17:45 # 1 REVIEW published: 06 October 2020 doi: 10.3389/fbioe.2020.577204 Photosymbiosis for Biomedical Applications Myra N. Chávez1†, Nicholas Moellhoff2†, Thilo L. Schenck2, José Tomás Egaña3* and Jörg Nickelsen1* 1 Molecular Plant Science, Department Biology I, Ludwig-Maximilians-Universität München, Munich, Germany, 2 Division of Hand, Plastic and Aesthetic Surgery, University Hospital, Ludwig Maximilian Universität München, Munich, Germany, 3 Institute for Biological and Medical Engineering, Schools of Engineering, Biological Sciences and Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile Without the sustained provision of adequate levels of oxygen by the cardiovascular system, the tissues of higher animals are incapable of maintaining normal metabolic activity, and hence cannot survive. The consequence of this evolutionarily suboptimal design is that humans are dependent on cardiovascular perfusion, and therefore highly susceptible to alterations in its normal function. However, hope may be at hand. Edited by: “Photosynthetic strategies,” based on the recognition that photosynthesis is the source Bruce Alan Bunnell, University of North Texas Health of all oxygen, offer a revolutionary and promising solution to pathologies related to Science Center, United States tissue hypoxia. These approaches, which have been under development over the past Reviewed by: 20 years, seek to harness photosynthetic microorganisms as a local and controllable Matjaž Jeras, source of oxygen to circumvent the need for blood perfusion to sustain tissue survival. University of Ljubljana, Slovenia Kar Wey Yong, To date, their applications extend from the in vitro creation of artificial human tissues to University of Alberta, Canada the photosynthetic maintenance of oxygen-deprived organs both in vivo and ex vivo, *Correspondence: while their potential use in other medical approaches has just begun to be explored.
    [Show full text]
  • Gene Content and Organization
    Photosynth Res DOI 10.1007/s11120-006-9122-4 REGULAR PAPER Complete nucleotide sequence of the freshwater unicellular cyanobacterium Synechococcus elongatus PCC 6301 chromosome: gene content and organization Chieko Sugita Æ Koretsugu Ogata Æ Masamitsu Shikata Æ Hiroyuki Jikuya Æ Jun Takano Æ Miho Furumichi Æ Minoru Kanehisa Æ Tatsuo Omata Æ Masahiro Sugiura Æ Mamoru Sugita Received: 30 August 2006 / Accepted: 6 December 2006 Ó Springer Science+Business Media B.V. 2006 Abstract The entire genome of the unicellular of the potential protein-coding genes showed cyanobacterium Synechococcus elongatus PCC 6301 sequence similarities to experimentally identified and (formerly Anacystis nidulans Berkeley strain 6301) predicted proteins of known function, and the prod- was sequenced. The genome consisted of a circular ucts of 35% of the genes showed sequence similarities chromosome 2,696,255 bp long. A total of 2,525 to the translated products of hypothetical genes. The potential protein-coding genes, two sets of rRNA remaining 9% of genes lacked significant similarities genes, 45 tRNA genes representing 42 tRNA species, to genes for predicted proteins in the public DNA and several genes for small stable RNAs were databases. Some 139 genes coding for photosynthesis- assigned to the chromosome by similarity searches and related components were identified. Thirty-seven computer predictions. The translated products of 56% genes for two-component signal transduction systems were also identified. This is the smallest number of such genes identified in cyanobacteria, except for marine cyanobacteria, suggesting that only simple signal transduction systems are found in this strain. The gene arrangement and nucleotide sequence of Synechococcus elongatus PCC 6301 were nearly & C.
    [Show full text]
  • Predicting the Metabolic Capabilities of Synechococcus Elongatus PCC 7942 Adapted to Different Light Regimes
    Research Article Predicting the metabolic capabilities of Synechococcus elongatus PCC 7942 adapted to different light regimes Jared T. Broddricka,b, David G. Welkiea, Denis Jalletc,1, Susan S. Goldena, Graham Peersc, and Bernhard O. Palssonb,† aDivision of Biological Sciences, University of California, San Diego, La Jolla, CA, USA, bDepartment of Bioengineering, University of California, San Diego, La Jolla, CA, USA, cDepartment of Biology, Colorado State University, Fort Collins, CO, USA ABSTRACT KEYWORDS There is great interest in engineering photoautotrophic metabolism to generate bioproducts of societal cyanobacteria, importance. Despite the success in employing genome-scale modeling coupled with flux balance analysis photosynthesis, to engineer heterotrophic metabolism, the lack of proper constraints necessary to generate biologically Synechococcus realistic predictions has hindered broad application of this methodology to phototrophic metabolism. Here elongatus, flux we describe a methodology for constraining genome-scale models of photoautotrophy in the cyanobacteria balance analy- Synechococcus elongatus PCC 7942. Experimental photophysiology parameters coupled to genome-scale sis, constraint flux balance analysis resulted in accurate predictions of growth rates and metabolic reaction fluxes at low and based modeling, high light conditions. Additionally, by constraining photon uptake fluxes, we characterize the metabolic cost of genome scale excess excitation energy. The predicted energy fluxes are consistent with known light-adapted phenotypes in modeling cyanobacteria. Finally, we leverage the modeling framework to characterize existing photoautotrophic and photomixtotrophic engineering strategies for 2,3-butanediol production in S. elongatus. This methodology, applicable to genome-scale modeling of all phototrophic microorganisms, can facilitate the use of flux balance analysis in the engineering of light-driven metabolism.
    [Show full text]
  • Hints at the Applicability of Microalgae and Cyanobacteria for the Biodegradation of Plastics
    sustainability Review Hints at the Applicability of Microalgae and Cyanobacteria for the Biodegradation of Plastics Giovanni Davide Barone 1,* , Damir Ferizovi´c 2 , Antonino Biundo 3,4 and Peter Lindblad 5 1 Institute of Molecular Biotechnology, Graz University of Technology, 8010 Graz, Austria 2 Institute of Analysis and Number Theory, Graz University of Technology, 8010 Graz, Austria; [email protected] 3 Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari, 70125 Bari, Italy; [email protected] 4 Interuniversity Consortium for Biotechnology (CIB), 70125 Bari, Italy 5 Department of Chemistry—Ångström Laboratory, Uppsala University, SE-751 20 Uppsala, Sweden; [email protected] * Correspondence: [email protected] Received: 30 October 2020; Accepted: 10 December 2020; Published: 14 December 2020 Abstract: Massive plastic accumulation has been taking place across diverse landscapes since the 1950s, when large-scale plastic production started. Nowadays, societies struggle with continuously increasing concerns about the subsequent pollution and environmental stresses that have accompanied this plastic revolution. Degradation of used plastics is highly time-consuming and causes volumetric aggregation, mainly due to their high strength and bulky structure. The size of these agglomerations in marine and freshwater basins increases daily. Exposure to weather conditions and environmental microflora (e.g., bacteria and microalgae) can slowly corrode the plastic structure. As has been well documented in recent years, plastic fragments are widespread in marine basins and partially in main global rivers. These are potential sources of negative effects on global food chains. Cyanobacteria (e.g., Synechocystis sp. PCC 6803, and Synechococcus elongatus PCC 7942), which are photosynthetic microorganisms and were previously identified as blue-green algae, are currently under close attention for their abilities to capture solar energy and the greenhouse gas carbon dioxide for the production of high-value products.
    [Show full text]
  • Plasticity of the Genomic Haplotype of Synechococcus Elongatus Leads to Rapid Strain Adaptation Under Laboratory Conditions Justin Ungerera, Kristen E
    LETTER LETTER REPLY TO ZHOU AND LI: Plasticity of the genomic haplotype of Synechococcus elongatus leads to rapid strain adaptation under laboratory conditions Justin Ungerera, Kristen E. Wendta, John I. Hendryb, Costas D. Maranasb, and Himadri B. Pakrasia,1 Zhou and Li (1) describe a classic phenomenon in mi- Considering the sequencing results reported by crobiology in which the genotypes of bacteria rapidly Zhou and Li (1), we find their report and that of Lou evolve to optimize growth under selective conditions. et al. (3) to be consistent with our original work (4). In the original paper describing the fast-growing cya- Zhou and Li report that the Synechococcus 2973 hap- nobacterium Synechococcus elongatus UTEX 2973, lotype (obtained from UTEX) lacks the atpA SNP, Yu et al. (2) described the genome sequence that de- whereas the premise of Lou et al.’s. report is that Syn- fines the strain. Since 2015, several colleagues who echococcus 7942 with only the atpA SNP grows at the obtained the strain directly from the original Pakrasi same rate as the Synechococcus 2973 strain. In our laboratory stock successfully replicated the 2-h dou- work, we show that Synechococcus 2973 with the bling time of the strain. Seemingly, specific loci affect- atpA SNP removed does grow at the same rate as ing growth rate and light tolerance rapidly interconvert Synechococcus 7942 with only the atpA SNP in- between alternative haplotypes based on the growth cluded (figure 1 of ref. 4). Sequencing results by Zhou conditions. This is confirmed by the sequencing results and Li show that Synechococcus 2973 in their labora- of Zhou and Li (1) who report that the sample in their tory has reverted the atpA SNP; thus, as our data laboratory has mutated toward the Synechococcus show, it grows at the same rate as Synechococcus 7942 haplotype via SNP conversion.
    [Show full text]
  • Taxonomic Evaluation of Cyanobacteria Using Morphological Characters and Molecular Phylogeny Using Cpcb and Cpca Gene Sequencing
    J. Algal Biomass Utln. 2015, 6 (2): 32- 39 Taxonomic evaluation of Cyanobacteria using cpcB and cpcA Gene Sequencing ISSN: 2229 – 6905 Taxonomic evaluation of Cyanobacteria using Morphological Characters and Molecular phylogeny using cpcB and cpcA Gene Sequencing Yogesh Pawar, Kruti Dave, Samruddha Phadnis and Ganesh Iyer Department of Life Science, Ramnarain Ruia College, Matunga, Mumbai-400019 Email: [email protected] Abstract A biodiversity study was conducted in Mumbai, Thane and Raigad districts. Six cyanobacterial genera (Cyanobacterium, Phormidium, Plantothrix, Spirulina, Synechococcus and Synechocystis) were selected for taxonomic study using morphological characters and molecular taxonomic identification. It was observed that morphological characters need a supporting sequencing data for taxonomic study. Phycocyanin gene was selected so that any contamination other than cyanobacteria can be eliminated. A phylogenetic tree was constructed using MEGA 6 software and observed that the genera Phormidium, Planktothrix and Spirulina are polyphyletic and need an reassessment in the class. Keywords: Cyanobacteria, Morphology, Phycocyanin gene sequencing, Phylogeny, Taxonomy, Introduction Cyanobacteria, also called as blue green algae, are the most primitive photosynthetic organisms on the earth. Due to its arrangement of genetic material they were often classified in bacterial group but they are now classified under Kingdom plantae because of the presence of photosystem I and II (Thajuddin, N and Subramanian, G., 2005). They are found in various habitats such as lakes, rivers, ponds, rain water puddles, moist soil, and on tree barks. They are not only free living but are also found in association with plants and other green algae. Cyanobacteria are also used as biofertilizers in agriculture (Mishra, U.
    [Show full text]
  • Snps Deciding the Rapid Growth of Cyanobacteria Are Alterable LETTER Jie Zhoua and Yin Lia,1
    LETTER SNPs deciding the rapid growth of cyanobacteria are alterable LETTER Jie Zhoua and Yin Lia,1 Cyanobacteria researchers are keen to understand cyanobacteria strains were grown under a high light why Synechococcus elongatus UTEX 2973 (Synecho- intensity of 500 μE or 800 μE, at 38 °C, with 5% CO2. coccus 2973) can grow more than two times faster Two independent experiments and sequencing were than Synechococcus elongatus PCC 7942 (Synecho- performed. coccus 7942), as their genome sequences share 99.8% To our great surprise, no SNP was found in the identity (1). atpA gene, in either S. 2973-1 or S. 7942 HL-1. E260D A recent paper in PNAS by Ungerer et al. (2) gives in Ppnk and Q121R/E134K in RpaA were found in S. an answer. The authors investigate the molecular de- 2973-1, which is consistent with what Ungerer et al. (2) terminants accounting for the rapid growth of Syne- describe for Synechococcus 2973, while Q121R in chococcus 2973. They believe that the rapid growth of RpaA was found in S. 7942 HL-1. This SNP is described Synechococcus 2973 is decided by four SNPs in three in Synechococcus 2973 (2), but not in Synechococcus proteins, namely C252Y in AtpA, E260D in Ppnk, and 7942 HL (3). Q121R/E134K in RpaA. In our laboratory, S. 7942 HL-1 grows as fast as S. In a separate study, Lou et al. (3) coincidently 2973-1 under a high light intensity of 500 μEor obtained a Synechococcus 7942 mutant (designated 800 μE, at 38 °C, with 5% CO2.
    [Show full text]
  • Research Article
    Ecologica Montenegrina 20: 24-39 (2019) This journal is available online at: www.biotaxa.org/em Biodiversity of phototrophs in illuminated entrance zones of seven caves in Montenegro EKATERINA V. KOZLOVA1*, SVETLANA E. MAZINA1,2 & VLADIMIR PEŠIĆ3 1 Department of Ecological Monitoring and Forecasting, Ecological Faculty of Peoples’ Friendship University of Russia, 115093 Moscow, 8-5 Podolskoye shosse, Ecological Faculty, PFUR, Russia 2 Department of Radiochemistry, Chemistry Faculty of Lomonosov Moscow State University 119991, 1-3 Leninskiye Gory, GSP-1, MSU, Moscow, Russia 3 Department of Biology, Faculty of Sciences, University of Montenegro, Cetinjski put b.b., 81000 Podgorica, Montenegro *Corresponding autor: [email protected] Received 4 January 2019 │ Accepted by V. Pešić: 9 February 2019 │ Published online 10 February 2019. Abstract The biodiversity of the entrance zones of the Montenegro caves is barely studied, therefore the purpose of this study was to assess the biodiversity of several caves in Montenegro. The samples of phototrophs were taken from various substrates of the entrance zone of 7 caves in July 2017. A total of 87 species of phototrophs were identified, including 64 species of algae and Cyanobacteria, and 21 species of Bryophyta. Comparison of biodiversity was carried out using Jacquard and Shorygin indices. The prevalence of cyanobacteria in the algal flora and the dominance of green algae were revealed. The composition of the phototrophic communities was influenced mainly by the morphology of the entrance zones, not by the spatial proximity of the studied caves. Key words: karst caves, entrance zone, ecotone, algae, cyanobacteria, bryophyte, Montenegro. Introduction The subterranean karst forms represent habitats that considered more climatically stable than the surface.
    [Show full text]
  • Genome Features and Biochemical Characteristics of a Robust, Fast
    www.nature.com/scientificreports OPEN Genome Features and Biochemical Characteristics of a Robust, Fast Growing and Naturally Received: 21 June 2018 Accepted: 26 October 2018 Transformable Cyanobacterium Published: xx xx xxxx Synechococcus elongatus PCC 11801 Isolated from India Damini Jaiswal1, Annesha Sengupta1, Sujata Sohoni1, Shinjinee Sengupta1,2, Ambarish G. Phadnavis1, Himadri B. Pakrasi3,4 & Pramod P. Wangikar1,2,5 Cyanobacteria provide an interesting platform for biotechnological applications due to their efcient photoautotrophic growth, amenability to genetic engineering and the ability to grow on non-arable land. An ideal industrial strain of cyanobacteria would need to be fast growing and tolerant to high levels of temperature, light, carbon dioxide, salt and be naturally transformable. In this study, we report Synechococcus elongatus PCC 11801, a strain isolated from India that fulflls these requirements. The physiological and biochemical characteristics of PCC 11801 under carbon and light-limiting conditions were investigated. PCC 11801 shows a doubling time of 2.3 h, that is the fastest growth for any cyanobacteria reported so far under ambient CO2 conditions. Genome sequence of PCC 11801 shows genome identity of ~83% with its closest neighbors Synechococcus elongatus PCC 7942 and Synechococcus elongatus UTEX 2973. The unique attributes of PCC 11801 genome are discussed in light of the physiological characteristics that are needed in an industrial strain. The genome of PCC 11801 shows several genes that do not have homologs in neighbor strains PCC 7942 and UTEX 2973, some of which may be responsible for adaptation to various abiotic stresses. The remarkably fast growth rate of PCC 11801 coupled with its robustness and ease of genetic transformation makes it an ideal candidate for the photosynthetic production of fuels and chemicals.
    [Show full text]
  • Geneart Synechococcus Engineering Kits
    USER GUIDE GeneArt® Synechococcus Engineering Kits For expression of recombinant proteins in Synechococcus elongatus Catalog Numbers A14259, A14263 Publication Number MAN0005339 Revision 2.0 For Research Use Only. Not for use in diagnostic procedures. Information in this document is subject to change without notice. DISCLAIMER LIFE TECHNOLOGIES CORPORATION AND/OR ITS AFFILIATE(S) DISCLAIM ALL WARRANTIES WITH RESPECT TO THIS DOCUMENT, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. TO THE EXTENT ALLOWED BY LAW, IN NO EVENT SHALL LIFE TECHNOLOGIES AND/OR ITS AFFILIATE(S) BE LIABLE, WHETHER IN CONTRACT, TORT, WARRANTY, OR UNDER ANY STATUTE OR ON ANY OTHER BASIS FOR SPECIAL, INCIDENTAL, INDIRECT, PUNITIVE, MULTIPLE OR CONSEQUENTIAL DAMAGES IN CONNECTION WITH OR ARISING FROM THIS DOCUMENT, INCLUDING BUT NOT LIMITED TO THE USE THEREOF. NOTICE TO PURCHASER: LIMITED USE LABEL LICENSE: Research Use Only The purchase of this product conveys to the purchaser the limited, non-transferable right to use the purchased amount of the product only to perform internal research for the sole benefit of the purchaser. No right to resell this product or any of its components is conveyed expressly, by implication, or by estoppel. This product is for internal research purposes only and is not for use in commercial applications of any kind, including, without limitation, quality control and commercial services such as reporting the results of purchaser’s activities for a fee or other form of consideration. For information on obtaining additional rights, please contact [email protected] or Out Licensing, Life Technologies Corporation, 5791 Van Allen Way, Carlsbad, California 92008.
    [Show full text]
  • Unprecedented Biomass and Fatty Acid Production by the Newly Discovered Cyanobacterium
    bioRxiv preprint doi: https://doi.org/10.1101/684944; this version posted June 27, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 1 Unprecedented biomass and fatty acid production by the newly discovered cyanobacterium 2 Synechococcus sp. PCC 11901 3 Artur Włodarczyka, Tiago Toscano Selãoa, Birgitta Norlinga and Peter J. Nixona,b 4 5 aSchool of Biological Sciences, Nanyang Technological University, Singapore 6 bSir Ernst Chain Building- Wolfson Laboratories, Department of Life Sciences, Imperial College London, S. 7 Kensington Campus, London, SW7 2AZ, UK 8 9 10 Corresponding authors: Artur Włodarczyk, School of Biological Sciences, Nanyang Technological 11 University, Singapore. E-mail: [email protected] 12 Peter J. Nixon, Sir Ernst Chain Building- Wolfson Laboratories, Department of Life Sciences, Imperial 13 College London, UK. E-mail: [email protected] 14 15 16 17 18 19 20 21 22 23 24 bioRxiv preprint doi: https://doi.org/10.1101/684944; this version posted June 27, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 25 Abstract 26 Cyanobacteria, which use solar energy to convert carbon dioxide into biomass, are potential solar 27 biorefineries for the sustainable production of chemicals and biofuels. However, yields obtained with 28 current strains are still uncompetitive compared to existing heterotrophic production systems.
    [Show full text]